best thing since sliced bread

a new invention that is likely to improve people’s lives significantly

something that is thought to be very good

Examples:

The invention of internet has changed the way we live; it is the best thing since sliced bread.

The way he was praising her – you would think that she was the best thing since sliced bread.

“Have you checked out this cool new app? I think its the best thing since sliced bread.”

Smartphones have become an indispensable part of our lives; they are the best thing since sliced bread.

Some gadgets are marketed like the best thing since sliced bread, but I think they are just expensive gizmos.

“My new assistant is so efficient! She is the best thing since sliced bread!”

I really love my new computer, its the best thing since sliced bread.

Origin: The phrase refers to the convenience achieved by the invention of sliced bread, as what was earlier done by hand was now being done by machines. In this exact form, the phrase was first used in America in the 1950s.